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 A192504 Ludic nonprime numbers. 5
 1, 25, 77, 91, 115, 119, 121, 143, 161, 175, 209, 221, 235, 247, 265, 287, 301, 329, 341, 361, 377, 407, 415, 437, 445, 475, 481, 493, 497, 517, 527, 535, 553, 565, 581, 595, 625, 667, 685, 697, 703, 707, 749, 775, 791, 803, 805, 835, 841, 851, 865, 893, 913 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Intersection of A018252 and A003309; A010051(a(n))*(1-A192490(a(n))) = 1. LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..1000 PROG (Haskell) a192504 n = a192504_list !! (n-1) a192504_list = filter ((== 0) . a010051) a003309_list (PARI) A192504(maxn, bflag=0)={my(Vw=vector(maxn, x, x+1), Vl=Vec([1]), vwn=#Vw, i, vj, L=List()); while(vwn>0, i=Vw[1]; Vl=concat(Vl, [i]);       Vw=vector((vwn*(i-1))\i, x, Vw[(x*i+i-2)\(i-1)]); vwn=#Vw); kill(Vw); vwn=#Vl; for(j=1, vwn, vj=Vl[j]; if(!isprime(vj), listput(L, vj))); kill(Vw); vwn=#L; if(bflag, for(i=1, vwn, print(i, " ", L[i]))); if(!bflag, return(Vec(L))); } \\ Anatoly E. Voevudko, Feb 28 2016 CROSSREFS Cf. A002808. Sequence in context: A042230 A189642 A221309 * A033658 A080699 A134153 Adjacent sequences:  A192501 A192502 A192503 * A192505 A192506 A192507 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jul 05 2011 STATUS approved

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Last modified December 3 14:22 EST 2020. Contains 338906 sequences. (Running on oeis4.)